An AC surface discharge type plasma display panel (hereinafter referred to as PDP), which is a typical AC type PDP, is formed of a front plate made of a glass substrate having scan electrodes and sustain electrodes provided thereon for a surface discharge, and a back plate made of a glass substrate having data electrodes provided thereon. The front plate and the back plate are disposed to face each other in parallel in such a manner that the electrodes on both plates form a matrix, and that a discharge space is formed between the plates. And the outer part of the plates thus combined is sealed with a sealing member such as a glass frit. Between the substrates, discharge cells partitioned by barrier ribs are formed, and phosphor layers are provided in the cell spaces formed by the barrier ribs. In a PDP with this structure, ultraviolet rays are generated by gas discharge and used to excite and illuminate phosphors for red, green and blue, thereby performing a color display (See Japanese Laid-Open Patent Application No. 2001-195990).
In this PDP, one field period is divided into a plurality of sub fields, and sub fields during which to illuminate phosphors are combined so as to drive the PDP for a gradation display. Each sub field consists of an initialization period, an address period and a sustain period. For displaying image data, each electrode is applied with signals different in waveform between the initialization, address and sustain periods.
In the initialization period, all scan electrodes are applied with, e.g. a positive pulse voltage so as to accumulate a necessary wall charge on a protective film provided on a dielectric layer covering the scan electrodes and the sustain electrodes, and also on the phosphor layers.
In the address period, all scan electrodes are scanned by being sequentially applied with a negative scan pulse, and when there are display data, a positive data pulse is applied to the data electrodes while the scan electrodes are being scanned. As a result, a discharge occurs between the scan electrodes and the data electrodes, thereby forming a wall charge on the surface of the protective film provided on the scan electrodes.
In the subsequent sustain period, for a set period of time, a voltage enough to sustain a discharge is applied between the scan electrodes and the sustain electrodes. This voltage application generates a discharge plasma between the scan electrodes and the sustain electrodes, thereby exciting and illuminating phosphor layers for a set period of time. In a discharge space where no data pulse has been applied during the address period, no discharge occurs, causing no excitation or illumination of the phosphor layers.
In this type of PDP, a large delay in discharge occurs during the address period, thereby making the address operation unstable, or completion of the address operation requires a long address time, thereby spending too much time for the address period. In an attempt to solve these problems, there have been provided a PDP in which auxiliary discharge electrodes are provided on a front plate, and a discharge delay is reduced by a priming discharge generated by an in-plane auxiliary discharge on the front plate side, and a method for driving the PDP (See Japanese Laid-Open Patent Application No. 2002-297091).
However, in these conventional PDPs, when the number of lines is increased as a result of achieved higher definition, more time must be spent for the address time and less time must be spent for the sustain period, thereby making it difficult to secure brightness when higher definition is achieved. Furthermore, when the partial pressure of xenon (Xe) is increased to achieve higher brightness and higher efficiency, a discharge initiation voltage rises, thereby making an initializing discharge unstable. This may cause a write error, thereby narrowing the driving voltage margin of a write operation.
The present invention, which has been contrived in view of the aforementioned problems, has an object of providing a PDP which stably generates a priming discharge, thereby making an initializing operation or an address operation stable, even when high definition is achieved or the partial pressure of xenon (Xe) is increased.